The cementation surface of the FDP was treated with resin monomer of the corresponding resin cement using a micro brush (Heliobond Ivoclar Vivadent, liechtenstein). The resin was left unpolymerized, shielded from light, for at least 5 minutes to allow the resin to penetrate and activate the IPN-phase of the polymethacrylate polymer matrix of the FRC framework.